Control and indication of railway switches



May 11, 1937. w. A. WOOD CONTROL AND INDICATION 0F RAILWAY SWOITCHES Filed March 22, 1935 INVENTOR Willar'dA. W006i. Q/2% H IS ATTORNEY Patented May 11, 1937 2,080,022.

UNITED STATES PATENT OFFICE CONTROL AND INDICATION or RAILWAY SWITCHES Willard A, Wood, Swissvale, Pa.,- assignor to The Union Switch & Signal Company, Swissvale, Pa., a corporation of Pennsylvania Application March 22, 1935, Serial No. 12,470 Claims (01. 246-3) My invention relates to railway switches, and 1917, to J. P. Coleman, for Railway traffic conhas for one object the provision of apparatus for trolling apparatus.

the control and indication of a switch from a Switch 3 operates contact arms II and I2 in distant point with a minimum number of line accordance with any usual and well-known man- 5 wires between, such point and the switch. ner. Contact .ll may be what I will term a three- 5 Another object of my invention is to provide position contact, That is, contact arm II is closed the aforementioned apparatus which will. inwith contact HA or IIB if and only if the switch elude but a single source of current and which will is either in its full normal or full reverse posinot include any rectifying or other current limittion, respectively. Contact l2, however, may be ing devices. what I will term atwo-position contact. That W A still further object of my invention is the is, contact arm I2 is closed with contact IZA or provision. of means for modifying the control of 123 when the switch is either in. its full normal the switch when the track adjacent the switch or full reverse position, respectively, and also becomes occupied by a car or train. when the switch is beyond its mid-position in I will describe one form of apparatus embodytransit towards such position. Contact arms ll 15 ing my invention, and, will then point out the and I2 at times control the indicating apparatus novel features thereof in claims. associated with the switch 3 and the control mag- The accompanying drawing is a diagrammatic nets N and R, respectively, as will be explained view showing one form of apparatus, embodying hereinafter. my inventions Switch valve K is controlled in part by a man- Referring to the drawing, the reference charually operable lever D which may be one of a acters l and IA designate the track rails of a number of such levers located in a control cabin stretch of railway track which is provided with at a point remote from switch 3. Lever D is 'a switch 3. Switch 3 as here shown is operated provided with contacts l5 and 16 which are closed by a motor M, which comprises a cylinder 5, conwith contacts 15A and ISA, respectively, when taining a reciprocable piston 6 operatively conthe lever D is in its normal position, and which nected with switch 3. Fluid under pressure, usare closed with contacts l5B and IE3, respectively, ually compressed air, is at times supplied to one when lever D is in its reverse position. end or the other end of cylinder 5. from a suitable The reference characters NL and RL designate source, not shown in the drawing, and the supswitch indicating devices adjacent the lever D, ply of such fluid is controlled by a switch valve which are here shown as a pair of electric lamps designated, in general, by the reference character and which correspond to the normal and reverse K. This valve comprises a normal magnet N and positions of the switch, respectively. That is,

a reverse magnet R. It will be noted that switch lamp NL is lighted when switch 3 is in its normal 3 is not provided with the usual switch locking position and lamp BL is lighted when the switch 35 mechanism and, therefore, switch3is not mechanis in its reverse position, provided, as will be ically locked in its extreme positions but is held explained hereinafter, that the lever D is in a in such positions by the air pressure in cylinder corresponding position and that the track adja- 5 acting on piston 6. cent the switch is unoccupied.

The reference character B designates a single It is sometimes desirable, when, the railway source of energy which ishere shown asa battery switch is to be operated from a point at some and which supplies current. for controlling the distance away, as in the present instance, to promoter M and the indicating apparatus associated vide apparatus for preventing operation of the with the switch. switch by the lever when a train is within a As sh wn in the wing, the sw ch occupies given distance of the switch. For thispurpose, its norm l p n If, W, reverse magnet, R section A-B is insulated from adjoining portions is energized, fluid pressure will, be supplied to of the stretch of track by means of insulated joints motor Mto operate switch 3, to. its, reverse. posi- 2, Track battery 4 is connected across the rails tion. If, when the switch occupies. its reverse adjacent one end of the section, and a track rer position, magnet N is energizedvalve Kwill suplay G is connected across the rails adjacent the ply fluid pressure to motor M to restore switch 3 opposite end of the section. Relay when deto its normal position. Oneform of switch valve energized, as will be explained hereinafter, prewhich will operate in the manner described is vents the control of the switch valve by th disclosed and claimed in Letters Patent of the lever D, prevents the lighting of either indication United States No. 1,238,888, issued September 4, lamp NL or RL and, furthermore, places the 55 magnets N and R under control by the two position contact arm l2.

As shown in the drawing, lever D occupies its normal position, section A-B is unoccupied, and switch 3 occupies its normal position. If the operator in charge of lever D wishes to reverse the switch, he reverses lever D. The closing of contact I53 of lever D completes a circuit over which current flows from battery P, through contact 5513, contact 2! of relay G, wire 22, reverse magnet R, and wire 20 back to battery P. Motor M is therefore actuated to move switch 3 to its reverse position.

If the operator wishes to restore switch 3 to its normal position, he returns lever D to its normal position, whereupon current flows frombattery P, through contact I5A of lever D, contact I 3 of relay G, wire l9, normal magnet N of switch valve K, and wire back to battery P. Motor N then restores switch 3 to its normal position.

The indication lamp NL may be energized by a circuit which includes the control circuit previously traced for the magnet N up to and including wire l9 and thence through contact ll-l IA, wire 26, front contact of relay G, contact ISA of lever D and lamp NL to battery P. When lever D is in its reverse position indication lamp RL may be energized by a circuit which includes the control circuit previously traced for the magnet R up to and including wire 22 and thence through contact III IB, wire 26, front contact 25 of relay G, contact IBB of lever'D and lamp RL to battery P.

It should be observed that the circuits for both the normal and the reverse control and indication of the switch, as just described, are carried over front contacts of relay G. If, therefore, a train occupies section AB, so that relay G is deenergized, switch 3 cannot be controlled by lever D and neither lamp NL nor lamp RL may be lighted.

The appartus is arranged in such manner that if relay G becomes deenergized after the operation of lever D, and while switch 3 is in transit,

- current will be supplied over an auxiliary circuit to the switch valve to move the switch to an extreme position, thereby preventing the possibility of a train or car moving into the switch when the points of the switch occupy their intermediate positions. This auxiliary circuit also energizes magnet N or R for causing motor M to hold switch 3 in a corresponding position while a train occupies section A-B.

The auxiliary circuit for supplying current to magnet N or R of valve K when relay G becomes deenergized, passes from battery P, through back contact 23 of relay G, wire 24, and thence through Contact I 2A or I2B of switch 3. In usual practice, relay G is placed either in the same control cabin as lever D, or in some other central location at a distance from the switch controlled by relay G. Relay G, however, may be placed at any convenient point between the lever D and the switch 3.

In explaining the operation of the auxiliary circuits shown in the accompanying drawing, I will assume that switch lever D has been moved to the reverse position, and that motor M is operating to move switch 3 to its reverse position. I will also assume that relay G becomes deenergized, as by the entrance of a train or car into section A-B, before movement of switch 3 is completed. If relay G becomes deenergized while contact I2-l2A of switch 3 is still closed, current from battery P will flow through back contact 23 of relay G, wire 24, contact Ill-42A of switch 3, normal magnet N, and wire 20 back to battery P. Switch 3 will therefore be restored to its normal position. If, however, contact l2l2B of switch 3 becomes closed before the deenergization of relay G, current will flow from battery P, back contact 23 of relay G, wire 24, contact I2l2B of switch 3, reverse magnet R, and wire 20 back to battery P. Motor M will therefore complete the movement of switch 3 to its reverse position.

Similarly, if relay G becomes deenergized after the operation of lever D from its reverse to its normal position, and while the switch is in transit, current will be supplied from battery P, over wire 24, to restore the switch to its reverse position or to complete the movement of the switch to its normal position, depending upon whether contact lZ-IZB or l2|2A of switch 3 is closed at the time relay G becomes deenergized.

Since no mechanical locking is provided for switch 3, it is free to move when trailed through by a car or train. In the event switch 3 should be forced from its initial position by a car trailing through the switch, the auxiliary circuit will become effective for causing the switch to move to the opposite position. That is, as soon as contact arm I2 is moved beyond its mid-position the initial magnet will become deenergized and the other magnet will become energized to cause the switch to move to a position to correspond to the movement of the car. For example, if the switch 3 is in its normal position and the section A-B becomes occupied by a car trailing through the switch soas to force the switch towards its reverse position, the switch 3 will assume such reverse position when the switch is moved sulficiently to close contact |2|2B. By this means I avoid possible derailment of the car which would result if the direction of the movement of the car should be reversed after the front truck but before the rear truck of the car passed over the switch.

It should be noted that with apparatus embodying my invention, the operation of lever D, while relay G is deenergized, does not afiect the apparatus. When relay G again becomes energized, however, the control of switch valve K will be restored to the switch lever D, and motor M will then be operated to move switch 3 to the position corresponding to that of lever D.

Apparatus embodying my invention is particularly suitable for, though not limited to, use in railway classification yards where a plurality of switches similar to switch 3 are controlled from a central control cabin. It will be plain, from the foregoing description, that my invention provides a reliable means for the control, indication and locking of such type of switches. My invention requires only five line wires between the control lever and the switch and provides for all the safeguards usually required in a classification yard system.

It will be noted that the apparatus embodying my invention uses a single require any rectifying or other current limiting devices which are usually required in systems of this character when five or less line wires are used. My invention, therefore, is simple and economical to install and maintain and, due to its simplicity, provides greater assurance against the possibility of failure to operate properly.

Although I have herein shown and described only one form of apparatus embodying my invention, it is understood that various changes and battery and does not modifications be made therein within the scope of the appended claims without departing from the spirit and scope of my invention.

Having thus described my invention, what I claim is:

1. In combination, a switch valve comprising a normal and a reverse magnet, a railway switch controlled by said valve, a relay controlled by trafiic conditions adjacent said switch, a manually operable lever having a normal and a reverse contact, a circuit for the normal magnet including the normal contact on said lever and a front contact of the relay, a circuit for the reverse magnet including the reverse contact on said lever and another front contact of said relay, a normal indication lamp and a reverse indication lamp, a circuit for the normal indication lamp including said normal contact on said lever and said first front contact of said relay, and a circuit for the reverse indication lamp including said reverse contact on said lever and said other front contact of said relay.

2. In combination, a switch valve comprising a normal and a reverse magnet, a railway switch controlled by said valve, a relay controlled by trafiic conditions adjacent said switch, a manually operable lever having a normal and a reverse contact, a normal indication lamp and a reverse indication lamp, a single source of energy, a circuit connecting said source with said normal magnet as well as a circuit connecting said source with said normal indication lamp each including the normal contact on said lever and a front contact of said relay, and a circuit connecting said source with said reverse magnet as well as a circuit connecting said source with said reverse indication lamp each including the reverse contact on said lever and a front contact of said relay.

3. In combination, a switch valve comprising a normal and a reverse magnet, a railway switch controlled by said valve, a relay controlled by traffic conditions adjacent said switch, a first switch contact closed when said switch is normal, a second switch contact closed when said switch is reversed, a first circuit for said normal magnet controlled by one front contact of said relay, a second circuit for said normal magnet including a back contact of said relay and passing from said back contact through said first switch contact and thence through the winding of said normal magnet, a first circuit for said reverse magnet controlled by another front contact of said relay, a second circuit for said reverse magnet including a back contact of said relay and passing from said back contact through said second switch contact and thence through the winding of said reverse magnet, a normal indication lamp, a reverse indication lamp, a circuit for said normal indication lamp governed in accordance with the condition of said switch and including said one front contact and a third contact of said relay, and a circuit for said reverse indication lamp governed in accordance with the condition of said switch and including said other front contact and said third contact of said relay.

4. In combination, a switch valve comprising a normal and a reverse magnet, a railway switch controlled by said valve, a relay controlled by traffic conditions adjacent said switch, a manually operable lever having a normal and a reverse contact, a two position circuit controller having a normal contact and a reverse contact, a first circuit for the normal magnet including only a normal contact on the lever and a front contact of the relay, a second circuit for the normal magnet including only a normal contact on said two position circuit controller and a back contact of the relay, a first circuit for the reverse magnet including only a reverse contact on the lever and a front contact of the relay, a second circuit for the reverse magnet including only a reverse contact on said two position circuit controller contact and a back contact of the relay, a three position circuit controller actuated in accordance with the position of the switch, and indicating apparatus controlled by said three position circuit controller as well as by said lever and by said relay.

5. In combination, a railway switch having normal and reverse positions, means for operating said switch including a normal magnet and a reverse magnet, a contact actuated by said switch, a manually operable circuit controlling lever having normal and reverse positions, a normal indication lamp and a reverse indication lamp, a circuit for said normal magnet including a normal contact of said lever, a circuit for said reverse magnet including a reverse contact of said lever, a circuit for said normal lamp including said normal contact of said lever and another normal contact of said lever as well as said switch-actuated contact when in normal position, and a circuit for said reverse lamp including said reverse contact of said lever and another reverse contact of said lever as well as said switchactuated contact when in reverse position.

WILLARD A. WOOD. 

